My prediction is that the "mother" won't have any plotlines at all and will basically be a throw-in on the very last episode of the show. It's just a matter of how long they can keep it going before they get cancelled.

I told my wife we were never watching "How I Never Met Your Mother" again. If you're going to base a show on a premise, then stick to the gawdamm premise. I've pretty much just been watching it for Barney anyway and his character jumped the shark when he banged Robin.